1. Field of the Invention
The present invention relates to a method for preparing a raw material for functional foods from barley or wheat seeds. More particularly, the present invention relates to a method for preparing a raw material for functional foods that exhibit antioxidant, antidiabetic and/or antiobesity activity, by vernalizing barley or wheat seeds or fermenting vernalized barley or wheat seeds.
2. Description of the Related Art
Temperature is a factor which has a great influence on the photoperiodism of various crops and plants. Particularly, temperature plays an important role in flowering and developing annual winter crops or biennial crops.
Many temperature plants must experience a period of low temperature or cold of from 2 to 6 weeks to initiate or accelerate the flowering process in the spring. For example, when winter-growing species (e.g., barley, wheat, etc.) are seeded in the spring, their germination is delayed or does not occur.
Trofim Denisovich Lysenko, a soviet agronomist, advanced the theory that the length of the vegetative period of plants is dependent on not only their inheritance but also the external environment that exists when the plant is growing. He asserted that the poor germination of winter-growing crops sowed in the spring is attributed to the condition of the temperature being high after sowing, based on the finding that when they are sowed after exposure to the prolonged cold, seeds of winter-growing crops could readily germinate like spring-growing crops.
The artificial low-temperature treatment which allows winter-growing species to be sowed in the spring is termed “vernalization”, and effective vernalization can be achieved at a temperature range of from 0 to 10° C.
Like photoperiodism, responses to cold exposure may be divided into qualitative and quantitative responses. Without the experience of the prolonged cold of winter, the species of qualitative responses show hibernalism, that is, the property of plants whereby they remain for an indefinitely long period in the phase of tillering without flowering stems while the species of quantitative response show delayed flowering.
Depending on treatment temperature, vernalization may be classified into low-temperature vernalization (0˜10° C.) and high-temperature vernalization (10˜30° C.). Also, there are two vernalization treatments according to the time of vernalization: seed vernalization and bulb vernalization which target pregerminated seeds and bulbs, respectively.
Winter-growing wheat plants such as barley, wheat, etc. are of the seed vernalization variety whereas cabbages and rapes are representative of bulb vernalization plants.
Lactic acid bacteria is the generic name for bacteria that utilize saccharides such as glucose as an energy source with the concomitant production of lactic acid. In the body, lactic acid bacteria show various beneficial functions including inhibiting the growth of harmful bacteria, bowel regulation, reducing the blood cholesterol level, anticancer activity, and ameliorating constipation and diarrhea. The genera that comprise lactic acid bacteria are at its core Streptococcus, Pediococcus, Leuconostoc, Lactobacillus, and Bifidobacterium. 
Lactic acid bacteria are applied to food processing, typically aiming at improving the preservability, favor and/or functionality of foods.
For example, Korean Patent Laid-Open Publication No. 2010-0092786 discloses the antidiabetic activity of the food prepared by fermenting an extract from a mixture of Ganoderma lucidum and bitter buckwheat with Lactobacillus. Korean Patent Laid-Open Publication No. 2010-0059278 discloses a method for manufacturing savor-improved tea by treatment with lactic acid bacteria. The inhibitory activity of soybean fermented by complex Kimchi lactic acid bacteria against food poisoning bacteria is described in Korean Patent Laid-Open publication No. 2010-0020123. Korean Patent Laid-Open Publication No. 2008-0074290 discloses the application of lactic acid bacteria to the production of a beverage made from birch tree fluid that has improved perservability.
Leading to the present invention, intensive and thorough research into functional foods, conducted by the present inventors, resulted in the finding that when subjected to vernalization and optionally fermentation with lactic acid bacteria, barley and wheat seeds were provided with various functionalities including antioxidant activity, antidiabetic activity and antiobesity activity, higher than those of germinated seeds.